﻿<!DOCTYPE html>
<html>
<head>
    <script language="javascript" src="jquery.min.js"></script>
    <script language="javascript">
        $(document).ready(function () {
            $("button").click(function () {
                $("p:first").addClass("one two");
            });
        });
    </script>
    <style type="text/css">
        .one {
            font-size: 120%;
            color: blue;
        }

        .two {
            background-color: yellow;
        }
    </style>
</head>
<body>
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    <p>ÎÚÒÂÏï¿ÚÏ¦ÑôÐ±¡£</p>
    <button>ÏòµÚÒ»¸öpÔªËØÌí¼ÓÁ½¸öÀà</button>
</body>
</html>

